Originally Posted by

**slapmaxwell1** OK for these next set of questions I am supposed to say whether or not the following equations are linear. my text gives this formula that I am supposed to match the equation with..I don't know I'm not getting it all the way.

well here are the equations..

1. (y''')^2 - 5y' +2y = x^(19)

2. (tan x)y'' + (sin x)^2*y' + (cos x)y = 0

3. x^2*y'' - xy' + 5y^2 = 18

1. This one is of the 3rd order and not linear, because there is no p(x)y term

2. i said this was linear and its of the second order

3. this is of the second order but not linear because there is no q(x) term.

i think the way i looked at these problems is not quite correct, so any help would be appreciated. thanks in advance

oh and the * means multiplication. thanks